You are answering a USMLE-style medical question. Question: A 12-year-old boy is brought to the emergency department for the evaluation of persistent bleeding from his nose over the past hour. The bleeding started spontaneously. He has no history of a similar episode. He takes no medications. There is no history of abnormal bleeding in the family. His vital signs are within normal limits. On examination, he is pressing a gauze against his left nostril while hyperextending his head. The gauze is stained with blood and upon withdrawal of the gauze blood slowly drips out of his left nostrils. There is no bleeding from the right nostril. The remainder of the physical examination shows no abnormalities. Which of the following is the most appropriate initial therapy? Options: A) Anterior packing and topical antibiotics B) Oxymetazoline nasal spray C) Placement of an epinephrine gauze in the left nostril D) Squeezing the nostrils manually for 10 minutes with the head elevated Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.